Crank-shaft.



GKLASCHE.

CRANK SHAFT.

Y y APUCATION FILED DEC. 3i. i914. 1,251,389. Patented Dec. 25, 1917..

Witnesses:

` I-m/ervtcJr-f4 f. OSC: rf La: e, g, bym

is ofltor-heilly.A

UNITED STATES OFFICE.

OSCAR LASCHE, OF CHARLOTTENBURG, GERMANY, ASSIGNOR T GENERAL ELECTRICCOMPANY, A CORPORATION 0F NEW YORK. l

CRANE-SHAFT.

Speclication of Letters Patent.

Patented Dec.- 25, 19t?.

Application led December 31, 1914. Serial No. 879,833. y

. To all whom t may concern:

Be it known that I, OSCAR LAs'cHn, asuhject of. the King of Saxony,residing at -Charlottenburg, Germany, have invented certain Anew and'useful Improvements in Crank-Shafts, of which the following is aspecification.

The present inve/ation relates' to multithrow crank shafts moreparticularly for tively long in order to afford the necessary- Theobject of the invention is to provide a crank shaft which isshorter inlength than those heretofore made and which at the same time ismaterially stronger at the points-where the greatest stresses occur.l

' For a consideration of what IA believeto Vbe novel and my invention,attention is directed to the accompanying description and the claims,appended thereto.

Referring'to lthe drawing, Figure .1 is a side elevation of amulti-throw crank shaft embodying my invention;,Fig. .Qis an end .Viewthereof taken ou line 2 2, Fig. 1; and Fig. 3 shows diagrammatically myimproved y shaft in connection' with an internal com- Referring bustionengine.

first to Fig. 3, 4 indicates the cylinders of a two-cylinder internalcomfI bustion engine and 5 the op ositely moving pistons. 6 indicates ainu tai-throw cran shaft having a central journal 7 and end journals 8and 9, eachsupported in a sitable bearing 10. Between the central andeach outside bearing the shaft is provided with three crank pins, acentral crank pin 11 to which'the lower pistons are connectedby theconnecting rods'12 and two louter crank pins 13 to which the upperpistons are connected by cross-heads '14 and side y rods 15.

Referring now particularly to 1, it

will be seen that the crank'pins 13 are made very short as related tothe crank nins 11 and that they are of greater diameter, `their diameterbeing such that they intersect or overlap thejournals. This overlappingof the crank pins with the journals is a very important feature of myinvention, as .it adds great strength at a point where strength isneeded, thereby materially increasing the margin of safety. At the sametime it permits the cheek plates 16 between the pins and the journals tobe made much narrower than the remainingl cheek plates 17 which alsotends'to shorten the over-all length of the shaft. The cheek plates 16and 17 form the crank arms of the crank shaft. It is through them thatthe Apower is transmitted.v If found desirable the journals may alsobe'made larger in diameter so as to obtaina-greater overlapping of thesamewith the pins.`

In Fig. 2-the extent of the overlapping of i the journals and crank pinsis very clearly shown, but it will be understood that the proportionofthe parts may be Varied t'o suit different conditions met with.

In accordance with the provisions of the' but I desire tohave itunderstood that the apparatus` shown is on] illustrative, and that theinvention can other means; l

What I claimas new and desire to secure by'Letters Patent of the UnitedStates, is,-

A. multi-throw crank shaft having crank lpins' displaced approximately180, and

journals, said crankpins and journals being connected to each other bycheek plates which formV the crankl arms of the shaft, the crank pinsadjacentthe journals being made relatively short as compared to theothers and of such diameter as to overlap with the journals, and thecheek plates between them being substantially narrower -than theremaining cheek plates.

In Witness whereof, I`have'hereunto set my hand this 23rd day ofNovember, 1914. OSCAR LASCI-IE. Witnesses:

ERICH BERLE, GUs'rAv HIELRooK.

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